Area Forecast Discussion
Issued by NWS Gaylord, MI

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FXUS63 KAPX 251405

Area Forecast Discussion
National Weather Service Gaylord MI
1005 AM EDT Tue Oct 25 2016

Issued at 1005 EDT Tue Oct 25 2016

Strong surface ridging remains over Michigan late this morning. A
few lake effect rain showers continue to stream into N/NW flow
areas of Eastern Upper and NW Lower Michigan...but are gradually
diminishing thanks to strengthening subsidence...dry air and
lowering inversion heights. This diminishing trend will continue
thru the balance of the day...finally coming to an end by late
afternoon. Expect another cool and mainly cloudy day across the
Northwoods...with some clearing taking place late in the day.
Afternoon highs will be mainly in the mid to upper 40s.


.SHORT TERM...(Today and tonight)
Issued at 350 AM EDT Tue Oct 25 2016

...Lake effect ending today, quiet tonight...

Overview: Pronounced closed upper low is located just off the Pac
NW with strong jet energy once again plowing into the west coast
of the CONUS. Downstream ridging resides through the central CONUS
with deeper troughing across the easter lakes and New England
regions. Strong surface high pressure stretches from Hudson Bay
through the Great Lakes and the eastern CONUS. North-northwesterly
flow persists across northern Michigan along with ongoing
scattered lake effect rain showers, primarily over parts of NW
lower Michigan.

Today, north-northwesterly low level flow will gradually diminish
through the day as surface ridge axis builds overhead. Scattered
to numerous lake effect rain showers will persist across parts of
NW lower Michigan through this morning. But weakening flow and
drying aloft should end all lake induced showers by mid to late
afternoon along with thinning/clearing cloud cover heading into
the evening. Otherwise, another day with high temps running a few
to several degrees below normal.

Tonight, thinning/clearing cloud cover continues through the
evening and into the overnight hours before thicker clouds begin
arriving late overnight. Along with light winds for a good part of
the night, there will be a good window of opportunity for
temperatures to drop into the upper 20s to lower 30s for many
areas, and middle 20s certainly possible for those cold spots.

Meanwhile, short wave trough and attending surface low expected
to deepen across the central and northern plains this evening and
edge into the Midwest and far western Great Lakes by morning.
Thickening cloud cover arrives late overnight and there may be
some light precip (should be rain) just inching into the Manistee
area toward morning.

.LONG TERM...(Wednesday through Monday)
Issued at 350 AM EDT Tue Oct 25 2016

High impact weather potential: Minimal - snow mixing in across
eastern Upper/higher elevations of northern Lower Wed. night.

Pattern synopsis/Expected evolution: A progressive pattern continues
across the majority of the CONUS throughout the forecast period.
Tonight, northern Michigan lies in a transition zone between ridging
centered over the Intermountain West and troughing anchored over the
East Coast. By Tuesday evening, a shortwave ejects from the Rockies
with lee side cyclogenesis ongoing, quickly racing east through
Thursday, providing increased precipitation potential across the
Great Lakes Wed-Thursday.

Wednesday - Wednesday night: Fairly decent global model guidance
agreement that aforementioned developing low pressure is centered
over central Iowa by 12z Wednesday. Some ~50 mile disagreement in
terms of the precip`s leading edge likely due to the degree of dry
air in place across the majority of northern MI. At the precip`s
onset across far southwestern areas Wed AM, there could be a few
snowflakes mixed in for some of the coolest spots. Precip continues
to spread across areas west of I-75/south of M-32 through noon,
struggling to overcome low-level dry air elsewhere.

Beyond Wednesday morning, guidance has regressed in its overall
agreement/consistency within the last 24 hours, especially the
GFS/GEM - now keeping the steadiest precip generally south of the
CWA with just scattered showers across most of the area through the
entire event. Not sold on that far of a southerly solution with
nearly all other deterministic guidance and the majority of ensemble
members suggesting precip continuing to spread north/east throughout
the remainder of Wednesday into Wed. night. Will continue the threat
for a mix of rain/snow Wed. night across E. U.P. and the higher
elevations of northern Lower (virtually no snow threat as you head
near the lake shores) from sunset through sunrise Thursday morning.
2 meter soil temps still hovering around 50 degrees along with low
temperatures toeing the 32-35 degree range should limit accumulation
possibilities to up to a half an inch for those locations that
consistently see snow mix in or flip over completely for brief
periods of time throughout the night.

Thursday - Thursday night: Low pressure continues to shift off to
the east throughout the day with showers lingering into the early
afternoon hours, especially east of I-75. Wouldn`t be shocked to see
a few more snowflakes mixing in across E. Upper during the early
morning, but should be shut off rather quickly thanks to a late
October sun angle/diurnal cycle. While PoP grids will reflect
synoptically driven precip diminishing, have opted to bump up
chances in NW flow lake effect areas Thursday afternoon despite
exiting synoptic support/moisture with lingering cool air overhead
(H8 temps of roughly -4 C and delta Ts of 18 C). A drying trend
everywhere is expected Thursday night as even lake effect is
expected to wind down as WAA takes over ahead of the next
approaching system from the west.

Extended (Friday through Monday)...

A fairly active pattern continues as return flow dominates Friday
ahead of the next approaching northern stream shortwave progged to
slide from the northern plains into the Great Lakes late Friday-
Friday night, once again increasing shower chances locally. Despite
high pressure settling atop the region to end the weekend into early
next week, cool air overhead may provide additional scattered/light
lake effect chances Saturday through Monday.


.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
Issued at 640 AM EDT Tue Oct 25 2016

Scattered rain showers will continue to impact parts of NW lower
Michigan, mainly the TVC terminal site. Overall VFR conditions
today, although brief periods of MVFR cigs are possible.

Clearing skies tonight with VFR conditions and light winds.


Issued at 350 AM EDT Tue Oct 25 2016

With weakening winds and waves this morning, should be able to
cancel remaining small craft advisories with 5 am issuance.
Lighter winds/waves then anticipated through the balance of the
day into tonight.

Winds will increase late tonight into Wednesday with another
round of small craft advisories likely needed for all areas
Wednesday. Low end gale force gusts are not out of the question,
especially on Lake Michigan. But will hold off on issuing any gale
headlines at this juncture.




LONG TERM...Gillen
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